Nicolas Granatino had signed a prenuptial contract in which he agreed not to make a claim against his wife, Katrin Radmacher, heiress of a German paper magnate, should they split up. Eight years and two children later, however, Granatino – a former banker, now academic, who himself is the son of a wealthy French industrialist – claimed for a hefty slice of Radmacher's estimated £150m fortune, confident that the contract would be deemed worthless because English law did not recognise prenuptial agreements.

The changing approach of the courts signals a move to close the divide between the law in England and that in most European countries – indeed, Lord Justice Thorpe noted yesterday that Radmacher and Granatino, regarded as well-informed and consenting adults when they entered into the agreement, were from European countries where prenups were binding, giving the case "all the hallmarks of internationality".

Some lawyers said the ruling signalled the end of London being viewed as the "divorce capital of the world", where people could use the courts to pursue extravagant claims.

However, it has also been criticised as a "staggering decision" given that the couple's children are very young. Nicola Harries, a partner in the family solicitors Stevens & Bolton, said: "The disparity in lifestyles that the children will experience between their parents' homes will be stark, to say the least."